An analytical model for jitter in IP networks

Abstract

Traditionally, IP network planning and design is mostly based on the average delay or loss constraints which can often be easily calculated. Jitter, on the other hand, is much more difficult to evaluate, but it is particularly important to manage the QoS of realtime and interactive services such as VoIP and streaming video. In this paper, we present simple formulas for the jitter of Poisson traffic in a single queue that can be quickly calculated . It takes into account the packets delay correlation and also the correlation of tandem queues that have a significant impact on the end-to-end jitter. We then extend them to the end-to-end jitter of a tagged stream based on a tandem queueing network. The results given by the model are then compared with event-driven simulations. We find that they are very accurate for Poisson traffic over a wide range of traffic loads and more importantly that they yield conservative values for the jitter so that they can be used in network design procedures. We also find some very counterintuitive results. We show that jitter actually decreases with increasing load and the total jitter on a path depends on the position of congested links on that path. We finally point out some consequences of these results for network design procedures.

An efficient algorithm for traffic flow optimization in MPLS networks

“…The values of delay and jitter produced by the problem (18-24) are higher comparing with those provided, respectively, by the problems (7)(8)(9)(10)(11) and (12)(13)(14)(15)(16)(17). Therefore, even if the optimization does not provide a best solution for both delay and jitter, it produce a compromise between this two performance measures.…”

“…In this study, we consider the delay and jitter model for Poisson traffic developed in [7]. The purpose of this work is to produce a simple formula for the end-to-end delay and jitter of Poisson traffic in a single queue and then extend the model for multiple queues defining a path.…”

“…The jitter of a tagged flow produced by a single node can be approximated by the following formula [7]:…”

Techno‐economic analysis of FiWi access networks based on optimized source packet traffic

“…In both cases, low QoE/QoS values are expected. It has been shown that jitter actually improves as the load ρ increases and that the jitter on a path depends on where the more congested links occur on that path, which is in strong contrast with other QoS measures such as delay or packet loss …”

“…In further analysis, it is considered that the arrival rate of the tagged flow takes values between these two extreme points . If the arrival process is given as Poisson λ k and under the assumption of intermediate arrival rate, the end‐to‐end jitter of a tagged flow produced by a single node can be approximated as presented in expressions , and . …”